
struct VertexInput {
     @location(positionLocation) position : vec2 <f32>,
}
struct VertexOutput {
     @builtin(position) position : vec4 <f32>,
     @location(0) uv : vec2 <f32>,
};
@vertex
fn main(input : VertexInput) -> VertexOutput {
     var output : VertexOutput;
     output.uv = input.position * 0.5 + 0.5;
     output.position = vec4 <f32> (input.position, 0.0, 1.0); ;
     return output;
}
